Tracking device location identification

ABSTRACT

A last known location of a tracking device can be determined by using location information received at a tracking system. A disconnection event is received at the tracking system indicating that a tracking device has disconnected from a mobile device. In response, the tracking system can generate a last known location for the tracking device. Other relevant location updates, such as recent locations of the mobile device or locations of other mobile devices that connect to the tracking device are collected and associated with the disconnection event. Based on the location updates, a last known location of the tracking device can be computed and stored.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/460,602, filed on Feb. 17, 2017, entitled “Tracking Device LocationIdentification,” which is incorporated by reference in its entirety.

BACKGROUND

This disclosure relates generally to tracking devices, and morespecifically, to determining a last known location for a tracking device

Electronic tracking devices have created numerous ways for people totrack the locations of people and/or objects. For example, a user canuse GPS technology to track a device remotely or determine a location ofthe user. In another example, a user can attach a tracking device to animportant object, such as keys or a wallet, and use the features of thetracking device to more quickly locate the object, (e.g., if it becomeslost).

However, traditional tracking devices and corresponding systems sufferfrom one or more disadvantages. For instance, if a tracking device islost, the limited wireless range of the tracking device prevents anowner of the tracking device from locating the tracking device fromoutside the range of the tracking device. Generating an accurate lastknown location of a tracking device can be important in allowing anowner to find a lost tracking device, for example, by narrowing the areato search for the tracking device. Existing methods for determining alast known location do not incorporate all available information toestimate the last known location, therefore improved methods for lastknown location determination are needed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example tracking system environment in which atracking device can operate, according to one embodiment.

FIG. 2 illustrates an example tracking system for use in a trackingsystem environment, according to one embodiment.

FIG. 3 illustrates an example user mobile device for use in a trackingsystem environment, according to one embodiment.

FIG. 4 illustrates an example community mobile device for use in atracking system environment, according to one embodiment.

FIG. 5 illustrates an example tracking device for use in a trackingsystem environment, according to one embodiment.

FIG. 6 illustrates an example environment for determining a trackingdevice location based on later mobile device location updates, accordingto one embodiment.

FIG. 7 illustrates an example environment for determining a trackingdevice location based on multiple reported locations, according to oneembodiment.

FIG. 8 is a flowchart illustrating an example process for filtering datafor determining a last known location of a tracking device, according toone embodiment.

FIG. 9 is a flowchart illustrating an example process for determiningthe last known location of a tracking device, according to oneembodiment.

The figures depict various embodiments of the present invention forpurposes of illustration only. One skilled in the art will readilyrecognize from the following discussion that alternative embodiments ofthe structures and methods illustrated herein may be employed withoutdeparting from the principles of the invention described herein.

DETAILED DESCRIPTION

Environment Overview

Embodiments described herein detail functionality associated with atracking device. A user can attach a tracking device to or enclose thetracking device within an object, such as a wallet, keys, a car, a bike,a pet, or any other object that the user wants to track. Or, a trackingdevice can be a device with a primary purpose unrelated to trackingfunctionality (e.g., a set of headphones, an electronic key, a wirelessspeaker, a fitness tracker, a camera) that has an integrated trackingcomponent that allows the device to be tracked. The user can then use amobile device (e.g., by way of a software application installed on themobile device) or other device or service to track the tracking device.For example, the mobile device can perform a local search for a trackingdevice. However, in situations where the user is unable to locate thetracking device using their own mobile device (e.g., if the trackingdevice is beyond a distance within which the mobile device and thetracking device can communicate), the user can leverage the capabilitiesof a community of users of a tracking device system as described below.

A tracking system (also referred to herein as a “cloud server,”“tracking server,” or simply “server”) can maintain user profilesassociated with a plurality of users of the tracking system. Thetracking system can associate each user within the system with one ormore tracking devices associated with the user (e.g., tracking devicesthat the user has purchased and is using to track objects owned by theuser, or devices that include a tracking component and have additionalnon-tracking features). If the user's tracking device, or the object towhich the tracking device is attached, becomes lost or stolen, the usercan send an indication that the tracking device is lost to the trackingsystem, which is in communication with one or more mobile devicesassociated with the community of users in communication with the system.The tracking system can set a flag indicating the tracking device islost. When one of a community of mobile devices that are scanning fornearby tracking devices and providing updated locations to the trackingsystem identifies a flagged tracking device, the tracking system canassociate the received location with the flagged tracking device, andrelay the location to a user of the tracking device, thereby enablingthe user to locate the lost tracking device. As used herein, “mobiledevice” can refer to a phone, tablet computer, or other connecteddevice, and can also refer to systems typically not consider mobile,such as servers, routers, gateways, access points, and specializedsystems configured to couple to tracking devices and report a locationof the tracking devices.

As used herein, “tracking device” can refer to any device configured tocommunicate with another device for the purpose of locating the trackingdevice. Tracking devices can be specialized or single-purpose devices(e.g., self-contained devices that include circuitry or components tocommunicate with another device). However, “tracking device” as usedherein can also refer to device or object with a different primaryfunction but with secondary tracking device functionality. For example,a wireless speaker can include tracking device components that allow auser to track and/or locate the wireless speaker. In some embodiments, atracking device platform can be established such that devices andobjects that satisfy one or more criteria can act as tracking deviceswithin a tracking device ecosystem. For instance, a tracking deviceprovider can provide an SDK or custom chipset that, when incorporatedinto an object or device, enable the object or device to function astracking devices, to communicate with other devices within the trackingdevice ecosystem, and to implement the functionalities described herein.

FIG. 1 illustrates an example tracking system environment in which atracking device can operate, according to one embodiment. Theenvironment of FIG. 1 includes a tracking system 100 communicativelycoupled to a mobile device 102 associated with the user 103 via a firstnetwork 108. The tracking system 100 is also communicatively coupled toa plurality of community mobile devices 104 a through 104 n(collectively referred to herein as “community mobile devices 104”)associated with a plurality of users 105 a through 105 n of the trackingsystem 100 (collectively referred to herein as “community users 105”)via the first network 108. As will be explained in more detail below,the tracking system 100 can allow the user 103 to manage and/or locate atracking device 106 associated with the user 103. In some embodiments,the tracking system 100 leverages the capabilities of community mobiledevices 104 to locate the tracking device 106 if the location of thetracking device is unknown to the user 103 and beyond the capabilitiesof mobile device 102 to track. In some configurations, the user 103 mayown and register multiple tracking devices 106. Although FIG. 1illustrates a particular arrangement of the tracking system 100, mobiledevice 102, community mobile devices 104, and tracking device 106,various additional arrangements are possible.

In some configurations, the user 103 may be part of the community ofusers 105. Further, one or more users 105 may own and register one ormore tracking devices 106. Thus, any one of the users within thecommunity of users 105 can communicate with tracking system 100 andleverage the capabilities of the community of users 105 in addition tothe user 103 to locate a tracking device 106 that has been lost.

The tracking system 100, mobile device 102, and plurality of communitymobile devices 104 may communicate using any communication platforms andtechnologies suitable for transporting data and/or communicationsignals, including known communication technologies, devices, media, andprotocols supportive of remote data communications.

In certain embodiments, the tracking system 100, mobile device 102, andcommunity mobile devices 104 may communicate via a first network 108,which may include one or more networks, including, but not limited to,wireless networks (e.g., wireless communication networks), mobiletelephone networks (e.g., cellular telephone networks), closedcommunication networks, open communication networks, satellite networks,navigation networks, broadband networks, narrowband networks, theInternet, local area networks, and any other networks capable ofcarrying data and/or communications signals between the tracking system100, mobile device 102, and community mobile devices 104. The mobiledevice 102 and community of mobile devices 104 may also be incommunication with a tracking device 106 via a second network 110. Thesecond network 110 may be a similar or different type of network as thefirst network 108. In some embodiments, the second network 110 comprisesa wireless network with a limited communication range, such as aBluetooth or Bluetooth Low Energy (BLE) wireless network. In someconfigurations, the second network 110 is a point-to-point networkincluding the tracking device 106 and one or more mobile devices thatfall within a proximity of the tracking device 106. In such embodiments,the mobile device 102 and community mobile devices 104 may only be ableto communicate with the tracking device 106 if they are within a closeproximity to the tracking device, though in other embodiments, thetracking device can use long-distance communication functionality (forinstance, a GSM transceiver) to communicate with either a mobile device102/104 or the tracking system 100 at any distance. In someconfigurations, the mobile device 102 and one or more community mobiledevices 104 may each be associated with multiple tracking devicesassociated with various users.

As mentioned above, FIG. 1 illustrates the mobile device 102 associatedwith the user 103. The mobile device 102 can be configured to performone or more functions described herein with respect to locating trackingdevices (e.g., tracking device 106). For example, the mobile device 102can receive input from the user 103 representative of information aboutthe user 103 and information about a tracking device 106. The mobiledevice 102 may then provide the received user information, trackingdevice information, and/or information about the mobile device 102 tothe tracking system 100. Accordingly, the tracking system 100 is able toassociate the mobile device 102, the user 103, and/or the trackingdevice 106 with one another. In some embodiments, the mobile device 102can communicate with the tracking device 106 and provide informationregarding the location of the tracking device to the user 103. Forexample, the mobile device 102 can detect a communication signal fromthe tracking device 106 (e.g., by way of second network 110) as well asa strength of the communication signal or other measure of proximity todetermine an approximate distance between the mobile device 102 and thetracking device 106. The mobile device 102 can then provide thisinformation to the user 103 (e.g., by way of one or more graphical userinterfaces) to assist the user 103 to locate the tracking device 106.Accordingly, the user 103 can use the mobile device 102 to track andlocate the tracking device 106 and a corresponding object associatedwith the tracking device 106. If the mobile device 102 is located beyondthe immediate range of communication with the tracking device 106 (e.g.,beyond the second network 110), the mobile device 102 can be configuredto send an indication that a tracking device 106 is lost to the trackingsystem 100, requesting assistance in finding the tracking device. Themobile device 102 can send an indication of a lost device in response toa command from the user 103. For example, once the user 103 hasdetermined that the tracking device 106 is lost, the user can provideuser input to the mobile device 102 (e.g., by way of a graphical userinterface), requesting that the mobile device 102 send an indicationthat the tracking device 106 is lost to the tracking system 100. In someexamples, the lost indication can include information identifying theuser 103 (e.g., name, username, authentication information), informationassociated with the mobile device 102 (e.g., a mobile phone number),information associated with the tracking device (e.g., a unique trackingdevice identifier), or a location of the user (e.g., a GPS location ofthe mobile device 102 at the time the request is sent).

The tracking system 100 can be configured to provide a number offeatures and services associated with the tracking and management of aplurality of tracking devices and/or users associated with the trackingdevices. For example, the tracking system 100 can manage informationand/or user profiles associated with user 103 and community users 105.In particular, the tracking system 100 can manage information associatedwith the tracking device 106 and/or other tracking devices associatedwith the user 103 and/or the community users 105.

As mentioned above, the tracking system 100 can receive an indicationthat the tracking device 106 is lost from the mobile device 102. Thetracking system 100 can then process the indication in order to help theuser 103 find the tracking device 106. For example, the tracking system100 can leverage the capabilities of the community mobile devices 104 tohelp find the tracking device 106. In particular, the tracking system100 may set a flag for a tracking device 106 to indicate that thetracking device 106 lost and monitor communications received from thecommunity mobile devices 104 indicating the location of one or moretracking devices 106 within proximity of the community mobile devices104. The tracking system 100 can determine whether a specific locationis associated with the lost tracking device 106 and provide any locationupdates associated with the tracking device 106 to the mobile device102. In one example, the tracking system may receive constant updates oftracking device 106 locations regardless of whether a tracking device106 is lost and provide a most recent updated location of the trackingdevice 106 in response to receiving an indication that the trackingdevice 106 is lost.

In some configurations, the tracking system 100 can send a locationrequest associated with the tracking device 106 to each of the communitymobile devices 104. The location request can include any instructionsand/or information necessary for the community mobile devices 106 tofind the tracking device 102. For example, the location request caninclude a unique identifier associated with the tracking device 106 thatcan be used by the community mobile devices 104 to identify the trackingdevice 106. Accordingly, if one of the community mobile devices 104detects a communication from the tracking device 106 (e.g., if thecommunity mobile device 104 is within range or moves within range of thecommunication capabilities of the tracking device 106 and receives asignal from the tracking device 106 including or associated with theunique identifier associated with the tracking device 106), thecommunity mobile device 104 can inform the tracking system 100. Usingthe information received from the community mobile devices 104, thetracking system 100 can inform the user (e.g., by way of the mobiledevice 102) of a potential location of the tracking device 106.

As shown in FIG. 1 and as mentioned above, the tracking system 100 cancommunicate with a plurality of community mobile devices 104 associatedwith corresponding community users 105. For example, an implementationmay include a first community mobile device 104 a associated with afirst community user 105 a, a second community mobile device 104 bassociated with a second community user 105 b, and additionalcommunication mobile devices associated with additional community usersup to an nth community mobile device 104 n associated with an nthcommunity user 105 n. The community mobile devices 104 may also includefunctionality that enables each community mobile device 104 to identifya tracking device 106 within a proximity of the community mobile device104. In one example, a first community mobile device 104 a withinproximity of a tracking device 106 can communicate with the trackingdevice 106, identify the tracking device 106 (e.g., using a uniqueidentifier associated with the tracking device 106), and/or detect alocation associated with the tracking device 106 (e.g., a location ofthe first mobile community device 104 a at the time of the communicationwith the tracking device 106). This information can be used to provideupdated locations and/or respond to a location request from the trackingsystem 100 regarding the tracking device 106. In some embodiments, thesteps performed by the first community mobile device 104 a can be hiddenfrom the first community user 105 a. Accordingly, the first communitymobile device 104 a can assist in locating the tracking device 106without bother and without the knowledge of the first community user 105a.

As mentioned above, the tracking system 100 can assist a user 103 inlocating a tracking device 106. The tracking device may be a chip, tile,tag, or other device for housing circuitry and that may be attached toor enclosed within an object such as a wallet, keys, purse, car, orother object that the user 103 may track. Additionally, the trackingdevice 106 may include a speaker for emitting a sound and/or atransmitter for broadcasting a beacon. In one configuration, thetracking device 106 may periodically transmit a beacon signal that maybe detected using a nearby mobile device 102 and/or community mobiledevice 104. In some configurations, the tracking device 106 broadcasts abeacon at regular intervals (e.g., one second intervals) that may bedetected from a nearby mobile device (e.g., community mobile device104). The strength of the signal emitted from the tracking device 106may be used to determine a degree of proximity to the mobile device 102or community mobile device 104 that detects the signal. For example, ahigher strength signal would indicate a close proximity between thetracking device 106 and the mobile device 102 and a lower strengthsignal would indicate a more remote proximity between the trackingdevice 106 and the mobile device 102, though in some embodiments, thetracking device 106 can intentionally vary the transmission strength ofthe beacon signal. In some cases, the strength of signal or absence of asignal may be used to indicate that a tracking device 106 is lost.

System Overview

FIG. 2 illustrates an example tracking system for use in a trackingsystem environment, according to one embodiment. As shown, the trackingsystem 100 may include, but is not limited to, an association manager204, a tracking device location manager 206, and a data manager 208,each of which may be in communication with one another using anysuitable communication technologies. It will be recognized that althoughmanagers 204-208 are shown to be separate in FIG. 2, any of the managers204-208 may be combined into fewer managers, such as into a singlemanager, or divided into more managers as may serve a particularembodiment.

The association manager 204 may be configured to receive, transmit,obtain, and/or update information about a user 103 and/or informationabout one or more specific tracking devices (e.g., tracking device 106).In some configurations, the association manager 204 may associateinformation associated with a user 103 with information associated witha tracking device 106. For example, user information and trackinginformation may be obtained by way of a mobile device 102, and theassociation manager 204 may be used to link the user information andtracking information. The association between user 103 and trackingdevice 106 may be used for authentication purposes, or for storing userinformation, tracking device information, permissions, or otherinformation about a user 103 and/or tracking device 106 in a database.

The tracking system 100 also includes a tracking device location manager206. The tracking device location manager 206 may receive and process anindication that the tracking device 106 is lost from a mobile device(e.g., mobile device 102 or community mobile devices 104). For example,the tracking system 100 may receive a lost indication from a mobiledevice 102 indicating that the tracking device 106 is lost. The trackingdevice location manager 206 may set a flag on a database (e.g., trackerdatabase 212) indicating that the tracking device 106 is lost. Thetracking device location manager 206 may also query a database todetermine tracking information corresponding to the associated user 103and/or tracking device 106. The tracking system 100 may obtain trackingdevice information and provide the tracking device information or otherinformation associated with the tracking device 106 to a plurality ofcommunity mobile devices 104 to be on alert for the lost or unavailabletracking device 106.

The tracking device location manager 206 may also receive a locationfrom one or more community mobile devices 104 that detect the trackingdevice 106, for instance in response to the community mobile devicereceiving a beacon signal transmitted by the tracking device 106,without the tracking device 106 having been previously marked as lost.In such embodiments, a user corresponding to the mobile device 102 canrequest a most recent location associated with the tracking device fromthe tracking system 100, and the location manager 206 can provide thelocation received from the community mobile device for display by themobile device 102. In some embodiments, the location manager 206provides the location of the tracking device 106 received from acommunity mobile device either automatically (for instance if thetracking device 106 is marked as lost) or at the request of a user ofthe mobile device 102 (for instance, via an application on the mobiledevice 102). The location manager 206 can provide a location of atracking device 106 to a mobile device 102 via a text message, pushnotification, application notification, automated voice message, or anyother suitable form of communication. In some embodiments, the trackingdevice location manager 206 determines and stores a last known locationfor a tracking device 106 in response to the tracking device 106disconnecting from a mobile device 102 or, in some implementations, acommunity mobile device 104. The last known location for a trackingdevice 106 can be used as the most recent location associated with thetracking device 106 if the tracking device has not recently connected toa mobile device 102 or community mobile device 104.

The tracking device location manager 206 may further manage providingindications about whether a tracking device 106 is lost or not lost. Forexample, as discussed above, the tracking device location manager 206may provide a location request to the community of mobile devices 104indicating that a tracking device 106 is lost. Additionally, uponlocation of the tracking device 106 by the user 103 or by one of thecommunity of users 105, the tracking device location manager 206 mayprovide an indication to the user 103, community user 105, or trackingsystem 100 that the tracking device 106 has been found, thus removingany flags associated with a tracking device and/or canceling anylocation request previously provided to the community of users 105. Forexample, where a user 103 sends an indication that the tracking device106 is lost to the tracking system 100 and later finds the trackingdevice 106, the mobile device 102 may provide an indication to thetracking system 100 that the tracking device 106 has been found. Inresponse, the tracking device location manager 206 may remove a flagindicating that the tracking device 106 is lost and/or provide anupdated indication to the community of users 105 that the trackingdevice 106 has been found, thus canceling any instructions associatedwith the previously provided location request. In some configurations,the notification that the tracking device 106 has been found may beprovided automatically upon the mobile device 102 detecting the trackingdevice 106 within a proximity of the mobile device 102. Alternatively,the notification that the tracking device 106 has been found may beprovided by the user 103 via user input on the mobile device 102. Inanother example, a known user (e.g., a friend or family member) withwhom the tracking device 106 has been shared may provide an indicationthat the tracking device 106 has been found.

The tracking system 100 additionally includes a data manager 208. Thedata manager 208 may store and manage information associated with users,mobile devices, tracking devices, permissions, location requests, andother data that may be stored and/or maintained in a database related toperforming location services of tracking devices. As shown, the datamanager 208 may include, but is not limited to, a user database 210, atracker database 212, permissions data 214, and location request data216. It will be recognized that although databases and data within thedata manager 208 are shown to be separate in FIG. 2, any of the userdatabase 210, tracker database 212, permissions data 214, and locationrequest data 216 may be combined in a single database or manager, ordivided into more databases or managers as may serve a particularembodiment.

The data manager 208 may include the user database 210. The userdatabase 210 may be used to store data related to various users. Forexample, the user database 210 may include data about the user 103 aswell as data about each user 105 in a community of users 105. Thecommunity of users 105 may include any user that has provided userinformation to the tracking system 100 via a mobile device 102, 104 orother electronic device. The user information may be associated with oneor more respective tracking devices 106, or may be stored without anassociation to a particular tracking device. For example, a communityuser 105 may provide user information and permit performance of trackingfunctions on the community mobile device 104 without owning or beingassociated with a tracking device 106. The user database 210 may alsoinclude information about one or more mobile devices or other electronicdevices associated with a particular user.

The data manager 208 may also include a tracker database 212. Thetracker database 212 may be used to store data related to trackingdevices. For example, the tracker database 212 may include tracking datafor any tracking device 106 that has been registered with the trackingsystem 100. Tracking data may include unique tracker identifications(IDs) associated with individual tracking devices 106. Tracker IDs maybe associated with a respective user 103. Tracker IDs may also beassociated with multiple users. Additionally, the tracker database 212may include any flags or other indications associated with whether aspecific tracking device 106 has been indicated as lost and whether anyincoming communications with regard to that tracking device 106 shouldbe processed based on the presence of a flag associated with thetracking device 106. Similarly, tracking data may include a last knownlocation of the tracking device 106.

The data manager 208 may further include permissions data 214 andlocation request data 216. Permissions data 214 may include levels ofpermissions associated with a particular user 103 and/or tracking device106. For example, permissions data 214 may include additional users thathave been indicated as sharing a tracking device 106, or who have beengiven permission to locate or receive a location of a tracking device106. Location request data 216 may include information related to alocation request or a lost indication received from the user 103 via amobile device 102.

FIG. 3 illustrates an example user mobile device for use in a trackingsystem environment, according to one embodiment. As shown, the mobiledevice 102 may include, but is not limited to, a user interface manager302, a location request manager 304, a database manager 306, and atracking manager 308, each of which may be in communication with oneanother using any suitable communication technologies. It will berecognized that although managers 302-308 are shown to be separate inFIG. 3, any of the managers 302-308 may be combined into fewer managers,such as into a single manager, or divided into more managers as mayserve a particular embodiment.

As will be explained in more detail below, the mobile device 102includes the user interface manager 302. The user interface manager 302may facilitate providing the user 103 access to data on a trackingsystem 100 and/or providing data to the tracking system 100. Further,the user interface manager 302 provides a user interface by which theuser 103 may communicate with tracking system 100 and/or tracking device106 via mobile device 102.

The mobile device 102 may also include a location request manager 304.The location request manager 304 may receive and process a request inputto the mobile device 102 to send an indication that a tracking device106 is lost to a tracking system 100. For example, the user 103 mayprovide an indication that a tracking device 106 is lost, unreachable,or otherwise unavailable, from the mobile device 102 via the userinterface manager 302, and the location request manager 304 may processthe lost indication and provide any necessary data to the trackingsystem 100 for processing and relaying a location request to other users105 over a network 108. In some configurations, an indication that atracking device 106 is lost is provided via user input. Alternatively,the indication may be transmitted automatically in response to themobile device 102 determining that a tracking device 106 is lost.

In addition, the location request manager 304 can request a location ofthe tracking device 106 without the tracking device 106 being identifiedas lost. For instance, a user can access a tracking device locationfeature of an application running on the mobile device 102 (for example,via the user interface manager 302), and the location request manager304 can request a most recent location of the tracking device 106 fromthe tracking system 100. The location request manager 304 can receivethe most recent location from the tracking system 100, and can displaythe most recent location via the user interface manager 302.

The mobile device 102 may also include a database manager 306. Thedatabase manager 306 may maintain data related to the user 103, trackingdevice 106, permissions, or other data that may be used for locating atracking device 106 and/or providing a request to a tracking system 100for locating one or more tracking devices 106 associated with the user103. Further, the database manager 306 may maintain any information thatmay be accessed using any other manager on the mobile device 102.

The mobile device 102 may further include a tracking manager 308. Thetracking manager 308 may include a tracking application (e.g., asoftware application) for communicating with and locating a trackingdevice 106 associated with the user 103. For example, the trackingmanager 308 may be one configuration of a tracking application installedon the mobile device 102 that provides the functionality for locating atracking device 106 and/or requesting location of a tracking device 106using a tracking system 100 and/or a plurality of community mobiledevices 104. As shown, the tracking manager 308 may include, but is notlimited to, a Bluetooth Low Energy (BLE) manager 310, a persistencemanager 312, a local files manager 314, a motion manager 316, a securestorage manager 318, a settings manager 320, a location manager 322, anetwork manager 324, a notification manager 326, a sound manager 328, afriends manager 330, a photo manager 332, an authentication manager 334,and a device manager 336. Thus, the tracking manager 308 may perform anyof the functions associated with managers 310-338, described inadditional detail below.

The BLE manager 310 may be used to manage communication with one or moretracking devices 106. The persistence manager 312 may be used to storelogical schema information that is relevant to the tracking manager 308.The local files manager 314 may be responsible for managing all filesthat are input or output from the mobile device 102. The motion manager316 may be responsible for all motion management required by thetracking manager 308. The secure storage manager may be responsible forstorage of secure data, including information such as passwords andprivate data that would be accessed through this sub-system. Thesettings manager 320 may be responsible for managing settings used bythe tracking manager 308. Such settings may be user controlled (e.g.,user settings) or defined by the tracking manager 308 for internal use(e.g., application settings) by a mobile device 102 and/or the trackingsystem 100. The location manager 322 may be responsible for all locationtracking done by the tracking manager 308. For example, the locationmanager 322 may manage access to the location services of the mobiledevice 102 and works in conjunction with other managers to persist data.The network manager 324 may be responsible for all Internetcommunications from the tracking manager 308. For example, the networkmanager 324 may mediate all Internet API calls for the tracking manager308. The notification manager 326 may be responsible for managing localand push notifications required by the tracking manager 308. The soundmanager 328 may be responsible for playback of audio cues by thetracking manager 308. The friends manager 330 may be responsible formanaging access to contacts and the user's social graph. The photomanager 332 may be responsible for capturing and managing photos used bythe tracking manager 308. The authentication manager 334 may beresponsible for handling the authentication (e.g., sign in or login) ofusers. The authentication manager 334 may also include registration(e.g., sign up) functionality. The authentication manager 334 furthercoordinates with other managers to achieve registration functionality.The device manager 336 may be responsible for managing the devicesdiscovered by the tracking manager 308. The device manager 336 mayfurther store and/or maintain the logic for algorithms related to devicediscovery and update.

FIG. 4 illustrates an example community mobile device for use in atracking system environment, according to one embodiment. As shown, thecommunity mobile device 104 may include, but is not limited to, a userinterface manager 402, a tracking device manager 404, a database manager406, and a tracking manager 408, each of which may be in communicationwith one another using any suitable communication technologies. The userinterface manager 402, database manager 406, and tracking manager 408illustrated in FIG. 4 may include similar features and functionality asthe user interface manager 302, database manager 306, and trackingmanager 308 described above in connection with FIG. 3. It will berecognized that although managers 402-408 are shown to be separate inFIG. 4, any of the managers 402-408 may be combined into fewer managers,such as into a single manager, or divided into more managers as mayserve a particular embodiment.

The community mobile device 104 may include a tracking device manager404. The tracking device manager 404 may facilitate scanning for nearbytracking devices 106. In some configurations, the tracking devicemanager 404 can continuously or periodically scan (e.g., once persecond) for nearby tracking devices 106. The tracking device manager 404may determine whether to provide an updated location of the nearbytracking device 106 to the tracking system 100. In some configurations,the tracking device manager 404 provides a location of a nearby trackingdevice 106 automatically. Alternatively, the tracking device manager 404may determine whether the location of the tracking device 106 has beenrecently updated, and may determine whether to provide an updatedlocation based on the last time a location of the tracking device 106has been updated (e.g., by the community mobile device 104). Forexample, where the community mobile device 104 has provided a recentupdate of the location of a tracking device 106, the tracking devicemanager 404 may decide to wait a predetermined period of time (e.g., 5minutes) before providing an updated location of the same trackingdevice 106.

In one configuration, the tracking device manager 404 may receive andprocess a location request or other information relayed to the communitymobile device 104 by the tracking system 100. For example, the trackingdevice manager 404 may receive an indication of a tracking device 106that has been indicated as lost, and provide a location of the trackingdevice 106 if it comes within proximity of the community mobile device104. In some configurations, the community mobile device 104 isconstantly scanning nearby areas to determine if there is a trackingdevice 106 within a proximity of the community mobile device 104.Therefore, where a tracking device 106 that matches information providedby the tracking system 100 (e.g., from the location request) comeswithin proximity of the community mobile device 104, the tracking devicemanager 404 may generate and transmit a response to the location requestto the tracking system 100, which may be provided to the user 103associated with the tracking device 106. Further, generating andtransmitting the response to the tracking request may be conditioned onthe status of the tracking device 106 being flagged as lost by themobile device 102 and/or the tracking system 100.

The tracking device manager 404 may additionally provide otherinformation to the tracking system 100 in response to receiving thetracking request. For example, in addition to providing a location ofthe community mobile device 104, the tracking device manager may providea signal strength associated with the location to indicate a level ofproximity to the location of the community mobile device 104 provided tothe user 103. For example, if a signal strength is high, the locationprovided to the user 103 is likely to be more accurate than a locationaccompanied by a low signal strength. This may provide additionalinformation that the user 103 may find useful in determining the preciselocation of tracking device 106.

As described above, the tracking device manager 404 may determinewhether to send a location within the proximity of the tracking device106 to the tracking system 100. The determination of whether to send alocation to the tracking system 100 may be based on a variety offactors. For example, a tracking device manager 404 may determine tosend a location of the tracking device 106 to a tracking system 100based on whether the detected tracking device 106 has been indicated aslost or if a tracking request has been provided to the community mobiledevice 104 for the particular tracking device 106. In someconfigurations, the community mobile device 104 may send an update of alocation of a tracking device 106 even if the tracking device 106 is notassociated with a current tracking request or if the tracking device 106is not indicated as lost. For example, where the location of a trackingdevice 106 has not been updated for a predetermined period of time, thecommunity mobile device 104 may provide an update of a tracking devicelocation to the tracking system 100, regardless of whether a trackingrequest has been received.

In some configurations, the community mobile device 104 may includeadditional features. For example, the community mobile device 104 mayallow a tracking system 100 to snap and download a photo using photofunctionality of the community mobile device 104. In someconfigurations, this may be an opt-in feature by which a community user105 permits a tracking system 100 to take a snap-shot and possiblyprovide a visual image of an area within a proximity of the trackingdevice 106.

FIG. 5 illustrates an example tracking device for use in a trackingsystem environment, according to one embodiment. The tracking device 106of FIG. 5 includes an interface 502, a transceiver 504, a controller506, one or more sensors 508, and a GPS unit 510. The transceiver 504 isa hardware circuit capable of both transmitting and receiving signals.It should be noted that in other embodiments, the tracking device 106includes fewer, additional, or different components than thoseillustrated in FIG. 5. For instance, tracking devices might not includethe GPS unit 510 and can still implement the functionalities describedherein.

The interface 502 provides a communicative interface between thetracking device 106 and one or more other devices, such as a mobiledevice 102. For instance, the interface 502 can instruct the transceiver504 to output beacon signals as described above (for example,periodically or in response to a triggering event, such as a detectedmovement of the tracking device 106). The interface 502 can, in responseto the receiving of signals by the transceiver 504 from, for instance,the mobile device 102, manage a pairing protocol to establish acommunicative connection between the tracking device 106 and the mobiledevice 102. As noted above, the pairing protocol can be a BLEconnection, though in other embodiments, the interface 502 can manageother suitable wireless connection protocols (such as WiFi, GlobalSystem for Mobile Communications or GSM, and the like).

The controller 506 is a hardware chip that configures the trackingdevice 106 to perform one or more functions or to operate in one oroperating modes or states. For instance, the controller 506 canconfigure the interval at which the transceiver broadcasts beaconsignals, can authorize or prevent particular devices from pairing withthe tracking device 106 based on information received from the devicesand permissions stored at the tracking device, can increase or decreasethe transmission strength of signals broadcasted by the transceiver, canconfigure the interface to emit a ringtone or flash an LED light, canenable or disable various tracking device sensors, can enable or disablea tracking device GPS unit, can enable or disable communicativefunctionality of the tracking device 106 (such as a GSM transmitter andreceiving), can configure the tracking device into a sleep mode or awakemode, can configure the tracking device into a power saving mode, andthe like. The controller 506 can configure the tracking device toperform functions or to operate in a particular operating mode based oninformation or signals received from a device paired with or attemptingto pair with the tracking device 106, based on an operating state orconnection state of the tracking device 106, based on user-selectedsettings, based on information stored at the tracking device 106, basedon a detected location of the tracking device 106, based on historicalbehavior of the tracking device 106 (such as a previous length of timethe tracking device was configured to operate in a particular mode),based on information received from the sensors 508 or the GPS 510, orbased on any other suitable criteria.

The sensors 508 can include motion sensors (such as gyroscopes oraccelerators), altimeters, orientation sensors, proximity sensors, lightsensors, or any other suitable sensor configured to detect anenvironment of the tracking device 106, a state of the tracking device106, a movement or location of the tracking device 106, and the like.The sensors 508 are configured to provide information detected by thesensors to the controller 506. The GPS unit 510 is configured to detecta location of the tracking device 106 based on received GPS signals, andis configured to provide detected locations to the controller 506.

Last Known Location Determination

As described herein, determining and storing a last known location for atracking device 106 can allow the tracking system 100 to provide anapproximate location of a tracking device 106 to one or more mobiledevices 102 or community mobile devices 104, even if the tracking device106 has not recently connected to a mobile device 102 or communitymobile device 104. In some embodiments, the mobile device 102 andcommunity mobile device 104 report events including location data to thetracking system 100. For example, mobile devices can report events tothe tracking system 100 periodically, or in response to any suitabletrigger, such as connecting to a tracking device 106, disconnecting froma tracking device 106, if location data becomes available for the mobiledevice 102, or for any other suitable reason. For example, a mobiledevice 102 (or community mobile device 104) can report a disconnectionevent to the tracking system 100 when the mobile device 102 disconnectsfrom a tracking device 106. A disconnection event can include variousinformation about the mobile device 102 and the tracking device 106 atthe time the tracking device 106 disconnected from the mobile device102. For example, a disconnection event can contain, for example, atimestamp, tracking device ID, location of the mobile device 102 whenthe disconnection event was reported, and a location accuracy of thelocation. A location may be reported in any suitable format, such as aset of latitude-longitude coordinates.

In some implementations, the tracking system 100 uses the location ofthe mobile device 102 included in the disconnection event as the lastknown location of the tracking device 106. In some implementations,because the mobile device 102 was connected to the tracking device 106,the location of the mobile device 102 can be used as an estimate of thelocation of the tracking device 106 at that time. In some cases, thelocation reported with the disconnection event accurately represents thelast known location of the tracking device 106. However, the locationreported in the disconnection event is not always the most accurateavailable location for the tracking device 106, nor do all disconnectionevents contain a useable location. For example, location services maynot be available for the mobile device 102 when the tracking device 106disconnects, or location data for the mobile device 102 can beinconsistent or inaccurate when the tracking device 106 disconnects (forexample, if the mobile device 102 is in a parking garage whichinterferes with GPS signals). Therefore, in some embodiments,determining the last known location for a tracking device 106 can bebased on reported location information from a variety of sources orotherwise require more calculation than finding the most recentlyreported location for the tracking device 106.

In some embodiments, locations reported by the mobile device 102 beforeor after the disconnect event can be used to infer a last known locationof the tracking device 106 at the time of the disconnection event.Similarly, a last known location for a tracking device 106 can bedetermined or improved based on locations reported by other mobiledevices 102 or community mobile devices 104 which recently connected tothe tracking device 106.

FIG. 6 illustrates an example environment for determining a trackingdevice location based on later mobile device location updates, accordingto one embodiment. The environment 600 of FIG. 6 includes an initialdevice location 610 with a corresponding initial location accuracy 615,a later device location 620 with a corresponding with a later locationaccuracy 625, and an estimate location accuracy 630.

In some embodiments, the initial device location 610 represents alocation of the mobile device 102 at an initial time, for example, alocation reported by the mobile device 102 in a disconnection event. Theinitial device location 610 is associated with a corresponding initiallocation accuracy 615 representing the potential deviation of the actualposition of the mobile device 102 from the reported initial devicelocation 610. The initial location accuracy 615 can be any suitablemeasure of the accuracy of the reported initial device location 610, forexample an expected deviation from the initial device location 610 or aradius of a circle within which the mobile device 102 is expected to belocated. The accuracy of a reported mobile device location can depend onavailable location services (for example, if a mobile device 102 has GPSdisabled, but a rough location is determined based on nearby WiFinetworks), natural variations or fluctuations in the reported location,environmental factors (for example, if the mobile device 102 is locatedin a parking structure or other building interfering with GPS signals),or any other suitable factor.

Over time, the mobile device 102 can report additional locations to thetracking system 100 in addition to the initial mobile device location610, according to some embodiments. For example, if the initial devicelocation 610 was reported in a disconnection event, the mobile device102 can continue to report location information to the tracking system100 in other events. A mobile device 102 can report a location to thetracking system 100 in response to a second disconnection event(associated with a different tracking device 106), periodically, whileconnected to a different tracking device 106, when connecting to thetracking system 100, or for any other suitable reason. In someimplementations, each location reported by a mobile device 102 isassociated with a location accuracy, which can vary based on, forexample, environmental factors or natural variations as described above.The later device location 620 and later location accuracy 625 representa relatively high accuracy location of the mobile device 102 reported ata time after the initial device location 610 was reported by the mobiledevice 102. For example, the later device location 620 can represent thelocation of the mobile device 102 25 seconds after the initial devicelocation 610. In the embodiment of FIG. 6, the later device location 620is more accurate than the initial mobile device location 610. Forexample, this could be due to the mobile device 102 reacquiring a GPSsignal between the time the initial device location 610 was reported tothe tracking system 100 and the time the later device location 620 wasreported to the tracking system 100.

When a later device location 620 is more accurate than the initialdevice location 610, the later device location 620 can be used togenerate a more accurate estimate of the location of the mobile device102 at the time the initial device location 610 was reported. Laterdevice location 620 can be used as the estimated location of the mobiledevice 102 at the initial time. In some embodiments, to determine theestimated location accuracy 630, the later location accuracy 625 isadjusted to account for the difference in time between the initialdevice location 610 and the later device location 620. For example, theestimated location accuracy 630 can take into account potential motionof the mobile device 102 in the intervening time between the initialdevice location 610 and the later device location 620. The laterlocation accuracy 625 can be adjusted based on any suitable factor togenerate the estimated device location 630, for example the differencein time between the initial and later device locations 610 and 620, thedifference in location between the initial and later device locations610 and 620, or any other suitable factor.

In the embodiment of FIG. 6, the estimated location accuracy 630represents the adjusted accuracy of the estimated device location. Insome embodiments, the estimated location accuracy 630 is more accuratethan the initial location accuracy 615 (even after the adjustment).Therefore, the later device location 620 and estimated location accuracy630 can be used as the last known location of the tracking device 106.Similar techniques can be used to determine a last known location for atracking device 106 from location information preceding thedisconnection event. In some embodiments, to be used as the last knownlocation of a tracking device 106, the later location accuracy 625 ofthe later device location 620 should be greater than a thresholdaccuracy and the later device location 620 should be reported within athreshold time of the disconnection event.

FIG. 7 illustrates an example environment for determining a trackingdevice location based on multiple reported locations, according to oneembodiment. The environment 700 of FIG. 7 includes a mobile device 710and associated mobile device location accuracy 715, a community mobiledevice A 720 and associated community mobile device A location accuracy725, a community mobile device B 730 and associated community mobiledevice B location accuracy 735, and an estimated tracking devicelocation 740 determined based on the reported locations.

In the embodiment of FIG. 7, the mobile device 710 and the communitymobile devices A 720 and B 730 each report (to the tracking system 100)a location associated with the same tracking device 106. Each reportedlocation can be associated with other relevant information, for example,a timestamp, a signal strength of the tracking device 106 at the timethe location was reported, and/or an accuracy of the reported location(for example, the mobile device location accuracy 715 and the communitymobile device location accuracies A 725 and B 735). In some embodiments,reported locations used to determine the location of a tracking device106 can be associated with various times, within a certain thresholdtime period of the time at which to estimate the location.

To estimate a location for a tracking device 106 from the knownlocations of mobile devices 102 and community mobile devices 104connected to the tracking device 106, a location determination algorithmcan be used, according to some embodiments. Each reported location (forexample, the locations of the mobile device 710 and the community mobiledevices A 720 and B 730) can be assigned a weight in the locationdetermination algorithm based on any suitable factors, for example thetimestamp of the reported location, the accuracy of the reportedlocation, and/or the strength of signal of the tracking device 106 atthe mobile device 102 (or community mobile device 104) when the locationwas reported. Any suitable location determination algorithm can be usedto determine the estimated tracking device location 740 based on one ormore reported locations. For example, a triangulation algorithm can beused to determine the estimated tracking device location 740, such as aDelaunay triangulation operation, a greedy triangulation operation, ajump-and-walk triangulation operation, a kinetic triangulationoperation, or the like. In other embodiments, the estimated trackingdevice location 740 can be determined by a weighted average of thereported locations of the mobile device 710 and the community mobiledevices A 720 and B 730, where each reported location is weighted basedon one or more of the location accuracy, signal strength, and time ofthe reported location. In some embodiments, the accuracy of theestimated location can be calculated by similar methods.

In order to determine a last known location for a tracking device 106,additional data reported about the tracking device 106 can be collectedand referenced to determine the last known location. However, a trackingsystem 100 may deal with large numbers of tracking devices 106, eachassociated with multiple mobile devices 102 and community mobile devices104 which in turn report events (such as disconnection events) includinglocation information and other relevant information the tracking system100 in a continuous stream of data. Collecting the relevant data neededto determine a last known location of a tracking device based on eachdisconnection event can require the tracking system to filter andorganize a large volume of data. Therefore, a “streaming” data systemcan be utilized to receive and organize relevant portions of datareceived at the tracking system 100 from a plurality of mobile devices102 and community mobile device 104 to determine a last known locationof a tracking device 106 for each disconnection event. In someimplementations, a data streaming framework (for example, Apache Sparkstreaming) can be used to filter and organize incoming data (includingdisconnection requests and location updates) to determine a last knownlocation. In some implementations, the data streaming framework allowsthe tracking system 100 to batch incoming data based on time and processeach batch of data individually. For example, the incoming data streamcan be separated and processed in batches of, for example, 20 seconds,or any other reasonable duration. In some embodiments, the duration ofeach batch is configurable, for example from 15-25 seconds.

FIG. 8 is a flowchart illustrating an example process for filtering datafor determining a last known location of a tracking device, according toone embodiment. In some implementations, the process 800 is followed foreach batch of data reported as part of a continuous data stream. Theprocess 800 begins when a stream of tracking device event information isreceived 810 at the tracking system. Then, the tracking system canseparate 820 events containing location updates from the receivedstream. For example, location updates can comprise the location of atracking device 106, mobile device 102, or community mobile device 104and may be reported in the context of a disconnection event (or anyother suitable event). In some implementations, disconnection events arealso separately handled (for example at step 830) and are not separatedas part of step 820. Information unnecessary for calculating a lastknown location of a tracking device 106 can then be removed 825 from theseparated location update data. For example, each event containing adevice location update can be reduced to a timestamp of the event, anidentifier of the reporting mobile device 102 (or community mobiledevice 104), an identifier of a connected tracking device 106 (ifpresent), a location of the reporting mobile device 102, a locationaccuracy of the reported location, a signal strength of the trackingdevice 106 at the reporting mobile device 102, and any other relevantinformation. For example, a MapReduce operation can be used to reducelocation updates to only relevant information for calculating a lastknown location. In some implementations, filtering each tracking devicelocation update to remove unnecessary information improves theperformance of the tracking system by reducing the volume of data neededto be stored to determine the last known location of a tracking device106.

Disconnection events can be similarly separated 830 from the receiveddata stream. Each disconnection event is then associated and grouped 840with relevant tracking device location updates. For example, thetracking system 100 can associate each tracking device disconnectionevent with the location updates associated with the same tracking device106 as the disconnection event and/or any other location updates fromthe reporting mobile device 102. The grouped location updates, includingany location updates from the disconnection event itself, can then beused to determine 850 the last known location for the disconnectedtracking device 106.

FIG. 9 is a flowchart illustrating an example process for determiningthe last known location of a tracking device, according to oneembodiment. The process 900 begins when a disconnection event andassociated location is received 910, for example at a tracking system.In some implementations, the disconnection event includes location data,but the associated location data can also comprise additional locationdata gathered from other mobile devices or from different points in timethan the disconnection event. For example, FIG. 8 discloses a processfor filtering and organizing disconnection events with relevant locationinformation. If relevant location data is available 920, the process 800can proceed with determining the last known location. For example,associated location data may need to be within a certain time window ofthe disconnection event, or have a threshold level of accuracy to beused to generate a last known location. In some embodiments, if nosuitable location data is available for the disconnection event, no lastknown location can be determined for the tracking device.

In the process 900, if multiple mobile devices (or community mobiledevices) are reporting location data for the tracking device 930, thereported location from each reporting mobile device can be combined 940to determine the last known location of the tracking device. Forexample, a triangulation algorithm or weighted average of the reportedlocations can be used, as described in relation to FIG. 7. In someimplementations, only one location from each reporting mobile device isused to calculate the last known location of the tracking device (forexample, the highest accuracy or the reported location closest in timeto the disconnection event).

In other cases, only one mobile device (or community mobile device)report relevant location data 930 about the tracking device. In thesecases, the location (or locations) reported by the mobile device can beused to calculate the last known location. First, the tracking systemcan modify 950 the accuracy of each reported location based on the timedifference between the location and the disconnection event (and anyother suitable factor). After each location is modified to account forthe time different, the tracking system can select 955 the best and/ormost accurate location as the last known location of the trackingdevice.

In either case, the last known location of the tracking device isreturned 960. For example, the last known location can then be storedwithin the tracking system for later use, sent to an owner of thetracking device, or used for any other suitable purpose.

ADDITIONAL CONSIDERATIONS

The foregoing description of the embodiments of the invention has beenpresented for the purpose of illustration; it is not intended to beexhaustive or to limit the invention to the precise forms disclosed.Persons skilled in the relevant art can appreciate that manymodifications and variations are possible in light of the abovedisclosure.

Any of the devices or systems described herein can be implemented by oneor more computing devices. A computing device can include a processor, amemory, a storage device, an I/O interface, and a communicationinterface, which may be communicatively coupled by way of communicationinfrastructure. Additional or alternative components may be used inother embodiments. In particular embodiments, a processor includeshardware for executing computer program instructions by retrieving theinstructions from an internal register, an internal cache, or othermemory or storage device, and decoding and executing them. The memorycan be used for storing data or instructions for execution by theprocessor. The memory can be any suitable storage mechanism, such asRAM, ROM, flash memory, solid state memory, and the like. The storagedevice can store data or computer instructions, and can include a harddisk drive, flash memory, an optical disc, or any other suitable storagedevice. The I/O interface allows a user to interact with the computingdevice, and can include a mouse, keypad, keyboard, touch screeninterface, and the like. The communication interface can includehardware, software, or a combination of both, and can provide one ormore interfaces for communication with other devices or entities.

Some portions of this description describe the embodiments of theinvention in terms of algorithms and symbolic representations ofoperations on information. These algorithmic descriptions andrepresentations are commonly used by those skilled in the dataprocessing arts to convey the substance of their work effectively toothers skilled in the art. These operations, while describedfunctionally, computationally, or logically, are understood to beimplemented by computer programs or equivalent electrical circuits,microcode, or the like. Furthermore, it has also proven convenient attimes, to refer to these arrangements of operations as modules, withoutloss of generality. The described operations and their associatedmodules may be embodied in software, firmware, hardware, or anycombinations thereof.

Any of the steps, operations, or processes described herein may beperformed or implemented with one or more hardware or software modules,alone or in combination with other devices. In one embodiment, asoftware module is implemented with a computer program productcomprising a computer-readable medium containing computer program code,which can be executed by a computer processor for performing any or allof the steps, operations, or processes described.

Embodiments of the invention may also relate to an apparatus forperforming the operations herein. This apparatus may be speciallyconstructed for the required purposes, and/or it may comprise ageneral-purpose computing device selectively activated or reconfiguredby a computer program stored in the computer. Such a computer programmay be stored in a non-transitory, tangible computer readable storagemedium, or any type of media suitable for storing electronicinstructions, which may be coupled to a computer system bus.Furthermore, any computing systems referred to in the specification mayinclude a single processor or may be architectures employing multipleprocessor designs for increased computing capability.

Embodiments of the invention may also relate to a product that isproduced by a computing process described herein. Such a product maycomprise information resulting from a computing process, where theinformation is stored on a non-transitory, tangible computer readablestorage medium and may include any embodiment of a computer programproduct or other data combination described herein.

Finally, the language used in the specification has been principallyselected for readability and instructional purposes, and it may not havebeen selected to delineate or circumscribe the inventive subject matter.It is therefore intended that the scope of the invention be limited notby this detailed description, but rather by any claims that issue on anapplication based hereon. Accordingly, the disclosure of the embodimentsof the invention is intended to be illustrative, but not limiting, ofthe scope of the invention, which is set forth in the following claims.

What is claimed is:
 1. A method for determining a last known location ofa tracking device, the method comprising: receiving, by a trackingserver from a first mobile device, a disconnection event indicating thata first tracking device has disconnected from the first mobile device,the disconnection event comprising an identifier of the first trackingdevice, a location of the first mobile device when the first trackingdevice disconnects from the first mobile device, and a first timestamprepresentative of a time of the disconnection; receiving, by thetracking server, a plurality of location updates from one or more mobiledevices of a plurality of mobile devices other than the first mobiledevice, each location update in response to a corresponding mobiledevice detecting the first tracking device and comprising a location ofthe corresponding mobile device when the corresponding mobile devicedetected the tracking device, a measure of accuracy of the location, theidentifier of the first tracking device, and a timestamp representativeof a time of the detection; selecting, by the tracking server, one ormore location updates of the plurality of location updates based atleast in part on the timestamp of the disconnection event and thetimestamps of the one or more location updates; determining, based onthe selected location updates and the disconnection event, a last knownlocation for the first tracking device; and storing, by the trackingsystem, the last known location in association with the first trackingdevice.
 2. The method of claim 1, wherein selecting one or more locationupdates of the plurality of location updates comprises: selecting, fromthe plurality of location updates, location updates including timestampswithin a threshold amount of time of the first timestamp.
 3. The methodof claim 1, wherein determining a last known location for the firsttracking device comprises: combining the location of each selectedlocation update and the location of the disconnection event to determinethe last known location for the first tracking device.
 4. The method ofclaim 3, wherein combining the location of each selected location updateand the location of the disconnection event comprises weighting one ormore of the locations of each selected location update by thecorresponding measure of accuracy of the location.
 5. The method ofclaim 3, wherein combining the location of each selected location updateand the location of the disconnection event comprising performing atriangulation operation on the location of each selected location updateand the location of the disconnection event to determine the last knownlocation of the first tracking device.
 6. The method of claim 3, whereincombining the location of each selected location update and the locationof the disconnection event comprises computing an updated location for aselected location update based on a difference between the timestamp ofthe selected location update and the first timestamp, and wherein thelast known location for the first tracking device is determined based atleast in part of the updated location.
 7. The method of claim 6, whereinthe updated location for a selected location update is computed basedadditionally on the measure of accuracy of the selected location update.8. The method of claim 1, wherein the last known location for the firsttracking device is determined based on an average location of thedisconnection event and, for each selected location update, the locationof the selected location update weighted by the measure of accuracy ofthe selected location updated.
 9. The method of claim 1, wherein thelast known location for the first tracking device is determined based onan average of the location of the disconnection event and, for eachselected location update, the location of the selected location updateweighted by an amount of time difference between the timestamp of theselected location update and the first timestamp.
 10. The method ofclaim 1, further comprising: receiving, by the tracking server from thefirst mobile device, a request for the last known location for the firsttracking device; and providing, by the tracking server to the firstmobile device, the last known location for the first tracking device.11. The method of claim 10, wherein the first mobile device isconfigured to modify a map interface displayed by the first mobiledevice to display the last known location for the first tracking device.12. The method of claim 10, wherein the first mobile device isconfigured to modify a map interface displayed by the first mobiledevice to display the last known location for the first tracking device.13. The method of claim 1, wherein the last known location for the firsttracking device is determined based on an average of the location of thedisconnection event and, for each selected location update, the locationof the selected location update weighted by an amount of time differencebetween the timestamp of the selected location update and the firsttimestamp.
 14. The method of claim 1, further comprising: receiving, bythe tracking server from the first mobile device, a request for the lastknown location for the first tracking device; and providing, by thetracking server to the first mobile device, the last known location forthe first tracking device.
 15. A method for determining a last knownlocation of a tracking device, the method comprising: receiving, by atracking server from a first mobile device, a disconnection eventindicating that a first tracking device has disconnected from the firstmobile device, the disconnection event comprising an identifier of thefirst tracking device, a location of the first mobile device when thefirst tracking device disconnects from the first mobile device, and afirst timestamp representative of a time of the disconnection;receiving, by the tracking server, one or more location updates from thefirst mobile device, each location update comprising a location of thefirst mobile device and a timestamp representative of a time after thetime of the disconnection; selecting, by the tracking server, one ormore of the location updates based at least in part on the timestamp ofthe disconnection event and the timestamps of the one or more locationupdates; determining, based on the selected location updates and thedisconnection event, a last known location for the first trackingdevice; and storing, by the tracking system, the last known location inassociation with the first tracking device.
 16. The method of claim 15,wherein selecting one or more location updates comprises: selecting,from the one or more location updates, location updates includingtimestamps within a threshold amount of time of the first timestamp. 17.The method of claim 15, wherein determining a last known location forthe first tracking device comprises: combining the location of eachselected location update and the location of the disconnection event todetermine the last known location for the first tracking device.
 18. Themethod of claim 17, wherein combining the location of each selectedlocation update and the location of the disconnection event comprisingperforming a triangulation operation on the location of each selectedlocation update and the location of the disconnection event to determinethe last known location of the first tracking device.
 19. The method ofclaim 17, wherein combining the location of each selected locationupdate and the location of the disconnection event comprises computingan updated location for a selected location update based on a differencebetween the timestamp of the selected location update and the firsttimestamp, and wherein the last known location for the first trackingdevice is determined based at least in part of the updated location. 20.The method of claim 19, wherein an updated location is computed for eachselected location update, and wherein the last known location for thefirst tracking device is determined based on each updated location.